scare someone shitless
US /skɛr ˈsʌmˌwʌn ˈʃɪtˌlɛs/
UK /skɛr ˈsʌmˌwʌn ˈʃɪtˌlɛs/

1.
把某人吓坏了, 把某人吓得屁滚尿流
to frighten someone very badly
:
•
The sudden loud noise scared me shitless.
突如其来的巨响把我吓坏了。
•
Watching that horror movie last night scared him shitless.
昨晚看那部恐怖电影把他吓坏了。